Projector lamp for motor vehicles



July 3, 1928.

C. C. BOHNER PROJECTOR LAMP FOR MOTOR VEHICLES Filed Jan. 5, 1927 5Sheets-Sheet INVENTOR C/yde C 50/2026?" z wmrw ATTORNEYS Jlily 3, 1928.1,675,690

0. c. BOHNER PROJECTOR LAMP FOR MOTOR VEHICLES Filed Jan. 5, 1927 sSheets-Sheet 2 INVENTOR "a. Clyde 6 fioizner BY W Y MM Q ATTORNEYS July3, 1928.

C. C. BOHNER PROJECTOR LAMP FOR MOTOR VEHICLES Filed Jan. 1927 3Sheets-Sheet INVENTOR 6/yde 6. 5072770" ATTORNEYS Patented July 3, 1928.

UNITED STATES I 1,675,690 PATENT OFFICE.

' CLYDE C. IBOHNER, OF EAST ORANGE. NEW JERSEY, ASSIGNOR TO TTUNG-SOLLAMP WORKS, 0F NEWARILCNEW JERSEY, A CORPORATION OF NEW JERSEY.

PROJECTOR LAMP FOR MOTOR VEHICLES.

This invention relates to a projector or head lamp for motor vehiclesand an incandescent lamp therefor.

The object of the invention is a novel projector or head lamp for motorvehicles which requires no initial focal adjustments upon the insertionof an electric lamp and which maintains permanently a fixed and properrelation between the incandescent lamp bulb and the reflecting orprojecting surface, and the invention includes an electric lamp bulbwhich may 'be used either with my novel projectorto obtain a permanentand fixed focal relation with reference to the reflecting surface, ormay be used with equal facility in the standard projector or head lampsnow being used on motor vehicles.

For a better understanding of the invention, reference may be had to theaccompanying drawings wherein:

Fig. 1 is a view partly in section of a head lamp or projector embodyingmy invention;

Fig.2 is an enlarged view of my novel lamp bulb and a reflector partbroken away;

Figs. 3 to 7 are views of modified projector structures, and

Fig. 8 illustrates a step in the manufacture of my novel electric lampbulb.

Referring to the drawings I have illustrated one embodiment of myinvention in Figs. 1 and 2, showing a projector or head lamp for motorvehicles, including a suitable reflector 1 and an incandescent lamp bulb2. The incandescent lamp bulb 2 has a concentrated filament 3 andaconical neck portion 4, the filament 3 being carried by a mount 5 whichis sealed into the glass bulb 2 in the usual manner. Thebulb 2 has itsfilament 3.positioned and located in position with the bulb withreference to a plane passing through the bulb neck, which plane is atright angles to the axis of the bulb and is designatedby the line 66. Inthis embodiment the bulb is supported entirely from the glass parts ofthe bulb and independently of any metallic base, and when the base isomitted the leadingin conductors 5 may be connected with any suitabledevice (omitted for convenience) for effect ing connections with anoutslde clrcuit. There is a fixed rear support 7 carried by thereflector 1 which support in the embodiment illustrated is intheform ofa ring engaging the bulb 2 at the points on the bulb neck disposedwithin the plane (S -6. The other support for the bulb is designated at8 and preferably also consists of a ring which engages the spherical endof the bulb so as to properly center and position the same withreference to the support 7 and the reflector. This support 8 must engageand grip the bulb 2 firmly and hold the same tightly against the ringsupport 7. In the particular embodiment shown this support 8 ispivotally carried at one side by a bent arm 9 which extends forwardlyfrom the rear of. the reflector 1. The other side of the ring support 8is held by an arm 10, as for example, being in the form of a clamppivoted at 11 to-the support 8 and having a catch at 12 for effecting aquick removal and replacement of the bulb. These supports 8, 9 and 10are preferably sufficiently resilient to avoid breakage of the bulb whenit is clamped in position. It is understood, how ever, that any suitableform of supporting means may be provided for holding the bulb 2 in itsproper position with respect to the support 7 engaging the conical neckat points contained within the plane o6.

In'the embodiment shown in Fig. 3 the lamp bulb is provided with astandard base 13 and the support forthe outer or en.

larged end of the bulb may be omitted. There is a support 14, however,which is in the form of a ring and corresponds to the support 7 of Fig.1, this support 14 engaging the conical portion of thebulb neck at theplanar points indicated by the line 66 when the lamp bulb is inposition. The support 14 is made integral with a rearwardly extendingsleeve or shell 15 which has a groove 16 into which fits the peripheraledge of the opening in the reflector 1. The socket for the base 13 isdesignated at 17 and is provided with the usual bayonet joint connection18. This socket is movably contained within the sleeve or shell 15 and acoil spring 19 engages the shoulder of the ring support 14 at one endand at the other end engages the inner end of the socket 17, therebynormally tending to urge the socket 17 in a direction to hold the lampbulb 2 tightly againstthe supporting member 14. The socket 17 may beprevented from turning in any suitable manner, as for example by meansof the spline 17 fitting in a keyway in the shell 15.

In theembodimentshown in Fig. 4 there is provided a supporting ringsimilar to the supporting ring 14 of Fig. 3 which ring is similarlycarried by the reflector 1. The socket 21 for the reception of the base13 is movable back and forth on the guides 22, the latter being carriedby the ring 20 and the socket 21 being provided with two guide members23 which function with guides 22 to permit the socket 21 to move backand forth, toward and away from the ring 20; a coil spring 21 surroundsthe inner end of the socket and engages at one end the ring 20 and atthe other end the inner guide 23 and thereby normally holds the bulb 2tightly against the ring 20 with the latter engaging the conical neckportion of the bulb 2 al0ng the plane 66 with reference to which line orplane the filament is originallyadjusted/ In both the modifications ofFigs. 3 and 4 the lamp bulb 2 may be inserted by moving the socketsforward against the tension of tion of the bulb 2 with its base thereinwith the bayonet joint fastened in the usual manner.

In the modification of Fig. 5, the holding ring 25 is carried by thereflector l in a similar manner to the ring 14 of Fig. 3 and the socket26 is slidably retained in the outer end of the shell 25" formedintegrally with the ring 25. The lamp casing is indicated at 27, and forproviding for the ready insertion of lamp bulbs 2 and the removal of thesame and for retaining the lamp bulb 2 in its proper position againstthe ring 25, there is provided an elongated retaining and push-rodmember 28 extending rearwardly from the socket 26 and through the lampcasmg 27, which member 28 has a screwthreaded end and an adjusting nut29 thereon whereby the socket 26 may be withdrawn in a backwarddirection to hold the lamp bulb 2 tightly against the ring. A stop 30 iscarried by the member 28 a short distance from the lamp casing to serveto limit the rearward movement of the socket 26. To remove or insert alamp bulb 2 it is only necessary to loosen and move the nut 29 so as topermit the socket 26 to be moved forward (by pushing on end of rod 28)sufliciently tightly against the holder 25, the latter engaging theconical portion of the bulb neck at points in the plane 6-6. The socket26' the projector.

may be moved forward for insertion of anthe shell 34 with no rotarymovement neces-- sary for fastening, the shell 34 being provided with aslot 34 for the accommodation of theusual fastening pin of the base. Thelamp bulb is retained in its position by a special ring support 35engaging the outer bulbous or enlarged portion of the bulb 2. The ringsupport 35 includes two end supporting and adjusting parts 36 havingopenings therein for the accommodation of the two supports 37 whichextend forwardly from the reflector 1 and the ring 33, the ends 36 ofthe support 35 having screw-threaded openings therein registering withthe openings for the accommodation of the arms 37, and there areprovided set screws 38 which are adaptedto be screwed home to engage thearms 37 and hold the lamp in the fixed adjusted position.

One advantage of this projector construction is that the lamp bulbs 2 donot require any initial focal adjustments with reference to thereflecting surface of the reflector 1, the filaments 3 having beenadjusted in the process of manufacture with reference to points of theconical neck contained in the plane 6-6 and the ring supports engagingthe conical parts of the bulb necks at these reference points. Thefilament always maintains a fixed and proper relation with respect tothe reflecting surface, there being no necessity for adjustments oradjustable parts in A true fixed focus projector is thereby provided andthe bulbs 2 may be of various and sundry shapes and dimensions.especially in the modifications shown in Figs. 3 to 6 inclusive, withoutnecessitating a change of projector construction. A

'further advantage of this construction is the added security of thesupport by reason of the shortening of the leverage by the ringsengaging the conical portions of the bulb necks at points disposed inthe plane 6-6.-

The bases 13 of thebulbs 2 are preferably 'also located and positionedon the lamp bulbs so as to bear a predetermined relation with referenceto the planar points of the bulb neck contained within the plane 6-6when they are based. vThe lamp bulbs 2 may therefore br usedinterchangeably either in the projector. illustrated to obtain apermanently fixed focal adjustment, or they may be used in the standardreflectors (not illustrated) wherein the bulb is supported entirely bythe base 13 and wherein there is no support corresponding to the ringsupports engaging the conical portions of the bulb necks in the plane66.

The filaments 3 of the lamp bulbs 2 may be positioned and located withreference to the bulb neck or the plane 66 passing through the bulb neckin any desirable manner, but I prefer the method illustrated in Fig. 8,according to which method the lamp bulbs have their filaments adjusteddurin the scaling-in of the mounts 5, that is, the necessary adjustmentsare ellected after the sealing-in operation and before the seals havecooled sufiiciently to become set.

Closely adjacent the sealing-in machine (not illustrated) and inconvenient reach of the operator, there is disposed an apparatusincluding a holder or gauge 40, which is adapted to receive the conicalneck 4 of the bulb 2 as the operator removes the same from thesealing-in machine, as for example by means of a suitable grippingholder 41. The holder is ring-like in form with a section removedtherefrom to permit the lateral positioning of the bulb neck therewithinand'includes a bearing or gauge edge 40 against which the reference lineor points (plane 6-6) of the bulb neck firmly rests. Another guide 42 ispositioned above the lamp bulb 2 and is of V shape for receiving thehandle of the holder 41 to assure the approximate alinement of theholder 41 and the bulb 2 with respect to the ring holder 40. Inconjunction therewith I have indicated diagrammatically in Fig. 8 anoptical projecting system for projecting an enlarged shadow image of thefilament 3 of the lamp bulb 2 upon a lighted screen 43. the lattercontaining the cross lines 44. and if desired, suitable boundary lines45 forming a closed rectangle within which an enlarged shadow image 3'of the filament 3 is projected when the filament 3 bears the correctrelation to that portion of the conical neck portion of the bulb 2bearing against the holder 01 gauge 40. The projector system includes astandard lens 46. a light source 47 disposed on the opposite side of thefilament 3 and the lamp bulb 2 from the lens 46, and the reflectingmirrors 48 arranged at rightangles to each other and at a substantialdistance from the lens 46 and the screen 43. The mirrors are arranged soas to reflect the image to the screen 43 which is disposed to one sideof the optical axis of the lens 46 and above the level thereof.Preferably the lamp bulb 2 is closely adjacent the lens 46 and the lightsource 47 may also be conveniently near thereto. An opaque screen 49 isindicated between the bulb 2 and the light source 47 and contains a slit50 in line with the filament of bulb 47, the filament 3 and the axis ofthe lens 46. The operator in charge of the mount sealing-in machinegrips by means of the holder 41 the bulb 2 while it is on the sealing-inmachine, and in the manner indicated in Fig. 8 inserts it in theposition indicated, while the seal is still plastic and hot with theconical neck planar reference line 66 bearing against the ring gauge 40and the handle of the holder 41 resting within the V shaped guide 42 toproperly aline the lamp bulb. Upon the insertion of the lamp bulb in theholder, an enlarged image 3 of the filament 3 is projected upon thescreen 43 and if this image 3 falls outside of the rectangle 45 or withthe apex of the V offset from the vertical gauge line 44, as for examplein any of those positions indicated in dotted lines, the filament 3 maybe readily and quickly brought to its accurate and predeterminedposition with reference to the reference line or that portion of thebulb neck bearing against the gauge 40 by manipulating the exhaust tube51, the correct position being indicated by the image 3 being containedwithin the rectangle 4.3 with the apex of its V disposed on the verticalline 44. Such manipulation and adjustment is made of course while thelamp bulb is held by one hand within the holder or gauge 40 t and canordinarily be effected before the seal has had time to cool and set. Infact, adjustment can be effected so quickly that it is desirable tofacilitate the speeding up of the cooling and setting of the plasticseal while within the holder 40. This is conveniently effected by littleair blasts playing upon the neck of the bulb and in the particular em- Ibodimentshown I have indicated a plurality of radially disposed blasts,these being directed from radially disposed openings 52 in the interiorof the ring 40 which openings lead to a suitable air source. By the aidof this cooling blast the plasticv seal becomes set almost immediatelyafter any adjustment of the filament mount which may be necessary. andthe latter adjustment can be made almost instantaneously after thepositioning of the bulb with its plastic seal within the gauge holder40. The method of adjustment and apparatus of Fig. 8 form the subjectmatter of application Ser. No. 73,303,'filed December 5, 1925. The lampbulbs which thus have their mounts sealed in and adjusted with referenceto the reference line of the conical neck will have approximately thesame adjustments within the special projectors illustrated in Figs. 7,the fixed ring holders of the projectors being of the same size as thering bearing edge 40 and being accurately located and fixed withreference to the focal points of the reflectors 1 in the originalmanufacture thereof.

It is understood that any usual and suitable gathering, spreading orother modifying lens or lenses may be used in conjunction with thereflector 1, these being omitted angles to the bulb axis, a centrallydisposed fixed rear support adapted to directly engage the conical partof the neck of the electric bulb and cooperating supporting 'meansholding said lamp tightly against the rear support with the latterengaging the neck at points disposed in the aforesaid plane. V.

2. In a projector lamp for motor vehicles, the combination of areflector and an electric incandescent lamp bulb having its filamentpositioned and definitely located with reference to points on theconical portion of the bulb neck which are disposed in a plane at rightangles to the bulb axis, with a rear ring support surrounding thereflector axis and engaging the conical part of the bulb neckat theaforesaid points and another support operative' to hold the bulb tightlyagainst said first support with the latter engaging the bulb at saidplanar points and the bulb neck disposed within the ring support.

3. In a projector lamp for motor vehicles the combination of a reflectorand an electric incandescent lamp bulb having its filament positionedand definitely located with reference to points, on the conical portionof the bulb neck which are disposed in a plane at right angles to thebulb axis, with a rear ring support surrounding the reflector axisandengaging the conical part of the bulb neck at the aforesaid points, asecond support engaging the bulb neck and disposed rearwardly of" therear ring support and operative to align the bulb and hold it tightlyagainst said ringsupport with the latter engaging the bulb at saidplanar points and the bulb neck disposed within the ring support.

4. In a projector lamp for motor vehicles the combination of a reflectorand an electric incandescent lamp bulb having its filament neck, and aspring disposed between said supports and operative to hold the bulbtightly against said ring support with the latter engaging the bulb atsaid planar points and the bulb neck disposed within the ring support.

5. Av projector or; head lamp for motor vehicles includin a casing, areflector supported therewithln, a fixed ring support disposed withinthe reflector, said ring support being fixed within an opening formed inthe rear of the reflector with the ring-support surrounding thereflector axis and having a forward bearing and supporting surface forsurrounding and engaging an incandescent lamp bulb at points about theconical part of the bulb neck in a plane at right angles to the bulbaxis, a second support disposed rearwardly of the ring support andmovable axially of the reflector with respect to the first support, andmeans extending rearthe latter may be moved axially of the reflector forthe purpose set forth.

6. A projector of the character set forth in claim 5 whereina-compression spring is disposed between the two supports for yieldinglyholding the lamp bulb firmly against the ring support. a

7. A projector of the character set forth in claim 5' wherein the ringsupport has a rearwardly extending sleeve and the second support is acylindrical sleeve disposed within the ring support sleeve.

In testimony whereof, I have signed my name to this specification.

- CLYDE C. BOHNER.

